[Objective] The aim was to provide basic reference for the use of H-FABP gene in marker-assisted selection of the breeding process of pig.[Method] Single-nucleotide polymorphisms of the H-FABP gene in Shanxi White pig...[Objective] The aim was to provide basic reference for the use of H-FABP gene in marker-assisted selection of the breeding process of pig.[Method] Single-nucleotide polymorphisms of the H-FABP gene in Shanxi White pig,Mashen pig,Large White pig,Landrace and Duroc were tested by PCR-SSCP,and the correlation between genotype and intramuscular fat content in pigs were analyzed.[Result] One polymorphism was found in the amplified region of intron 1 of porcine H-FABP gene,in which two alleles(A and B)and three genotypes(AA,AB,and BB)were examined.C→T transition was detected by sequencing the homozygotes.The multiple comparison of the distribution of genotype in different pig varieties revealed that Mashen pig showed extremely significant difference(P0.01)in genotype distribution with Shanxi White,Landrace,Large White and Duroc breeds;whereas no significant differences(P0.05)were found in genotype distribution between other breeds.Based on the fixed effect model,extremely significant differences(P 0.01)were found in the intramuscular fat content among different H-FABP genotypes.Using least square analysis,it was found that there was significant differences(P 0.05)in the intramuscular fat content between the individuals of the BB genotypes and those of the AA genotypes.[Conclusion] The H-FABP genotype had significant effects on the meat quality.展开更多
Nearly half of the global population are carriers of Helicobacter pylori(H. pylori),a Gram-negative bacterium that persists in the healthy human stomach. H. pylori can be a pathogen and causes development of peptic ul...Nearly half of the global population are carriers of Helicobacter pylori(H. pylori),a Gram-negative bacterium that persists in the healthy human stomach. H. pylori can be a pathogen and causes development of peptic ulcer disease in a certain state of the macroorganism. It is well established that H. pylori infection is the main cause of chronic gastritis and peptic ulcer disease(PUD). Decontamination of the gastric mucosa with various antibiotics leads to H. pylori elimination and longer remission in this disease. However,the reasons for repeated detection of H. pylori in recurrent PUD after its successful eradication remain unclear. The reason for the redetection of H. pylori in recurrent PUD can be either reinfection or ineffective anti-Helicobacter therapy. The administration of antibacterial drugs can lead not only to the emergence of resistant strains of microorganisms,but also contribute to the conversion of H. pylori into the resting(dormant) state. The dormant forms of H. pylori have been shown to play a potential role in the development of relapses of PUD. The paper discusses morphological H. pylori forms,such as S-shaped,C-shaped,U-shaped,and coccoid ones. The authors proposes the classification of H. pylori according to its morphological forms and viability.展开更多
The Jimo coast encompasses an area of 2157 km^2, and the ecosystem is valuable both socially and economically with regional fisheries substantially contributing to the value. A mass-balanced trophic model consisting o...The Jimo coast encompasses an area of 2157 km^2, and the ecosystem is valuable both socially and economically with regional fisheries substantially contributing to the value. A mass-balanced trophic model consisting of 15 functional ecological groups was developed for the coastal ecosystem using the Ecopath model in Ecopath with Ecosim(Ew E) software(version 6.4.3). The results of the model simulations indicated that the trophic levels of the functional groups varied between 1.0 and 3.76, and the total production of the system was estimated to be 5112.733 t km^(-2) yr^(-1) with a total energy transfer efficiency of 17.6%. The proportion of the total flow originating from detritus was estimated to be 48%, whereas that from primary producers was 52%, indicating that the grazing food chain dominated the energy flow. The ratio of total primary productivity to total respiration in the system was 3.78, and the connectivity index was 0.4. The fin cycling index and the mean path length of the energy flow were 4.92% and 2.57%, respectively, which indicated that the ecosystem exhibits relatively low maturity and stability. The mixed trophic impact(MTI) procedure suggested that the ecological groups at lower trophic levels dominated the feeding dynamics in the Jimo coastal ecosystem. Overfishing is thought to be the primary reason for the degeneration of the Jimo coastal ecosystem, resulting in a decline in the abundance of pelagic and demersal fish species and a subsequent shift to the predominance of lower-trophic-level functional groups. Finally, we offered some recommendations for improving current fishery management practices.展开更多
By End(G) and hEnd(G) we denote the set of endomorphisms and half-strong endomorphisms of a graph G respectively. A graph G is said to be E-H-unretractive if End(G) = hEnd(G). A general characterization of an ...By End(G) and hEnd(G) we denote the set of endomorphisms and half-strong endomorphisms of a graph G respectively. A graph G is said to be E-H-unretractive if End(G) = hEnd(G). A general characterization of an E-H-unretractive graph seems to be difficult. In this paper, bipartite graphs with E-H-unretractivity are characterized explicitly.展开更多
基金Supported by Scientific Research Start Project of Hebei United University(07101168)~~
文摘[Objective] The aim was to provide basic reference for the use of H-FABP gene in marker-assisted selection of the breeding process of pig.[Method] Single-nucleotide polymorphisms of the H-FABP gene in Shanxi White pig,Mashen pig,Large White pig,Landrace and Duroc were tested by PCR-SSCP,and the correlation between genotype and intramuscular fat content in pigs were analyzed.[Result] One polymorphism was found in the amplified region of intron 1 of porcine H-FABP gene,in which two alleles(A and B)and three genotypes(AA,AB,and BB)were examined.C→T transition was detected by sequencing the homozygotes.The multiple comparison of the distribution of genotype in different pig varieties revealed that Mashen pig showed extremely significant difference(P0.01)in genotype distribution with Shanxi White,Landrace,Large White and Duroc breeds;whereas no significant differences(P0.05)were found in genotype distribution between other breeds.Based on the fixed effect model,extremely significant differences(P 0.01)were found in the intramuscular fat content among different H-FABP genotypes.Using least square analysis,it was found that there was significant differences(P 0.05)in the intramuscular fat content between the individuals of the BB genotypes and those of the AA genotypes.[Conclusion] The H-FABP genotype had significant effects on the meat quality.
文摘Nearly half of the global population are carriers of Helicobacter pylori(H. pylori),a Gram-negative bacterium that persists in the healthy human stomach. H. pylori can be a pathogen and causes development of peptic ulcer disease in a certain state of the macroorganism. It is well established that H. pylori infection is the main cause of chronic gastritis and peptic ulcer disease(PUD). Decontamination of the gastric mucosa with various antibiotics leads to H. pylori elimination and longer remission in this disease. However,the reasons for repeated detection of H. pylori in recurrent PUD after its successful eradication remain unclear. The reason for the redetection of H. pylori in recurrent PUD can be either reinfection or ineffective anti-Helicobacter therapy. The administration of antibacterial drugs can lead not only to the emergence of resistant strains of microorganisms,but also contribute to the conversion of H. pylori into the resting(dormant) state. The dormant forms of H. pylori have been shown to play a potential role in the development of relapses of PUD. The paper discusses morphological H. pylori forms,such as S-shaped,C-shaped,U-shaped,and coccoid ones. The authors proposes the classification of H. pylori according to its morphological forms and viability.
基金the financial support provided by the National Social Science Foundation (Grant No.12JJD790032)the Project of the Chinese Ministry of Education (Grant No.13JJD790032)
文摘The Jimo coast encompasses an area of 2157 km^2, and the ecosystem is valuable both socially and economically with regional fisheries substantially contributing to the value. A mass-balanced trophic model consisting of 15 functional ecological groups was developed for the coastal ecosystem using the Ecopath model in Ecopath with Ecosim(Ew E) software(version 6.4.3). The results of the model simulations indicated that the trophic levels of the functional groups varied between 1.0 and 3.76, and the total production of the system was estimated to be 5112.733 t km^(-2) yr^(-1) with a total energy transfer efficiency of 17.6%. The proportion of the total flow originating from detritus was estimated to be 48%, whereas that from primary producers was 52%, indicating that the grazing food chain dominated the energy flow. The ratio of total primary productivity to total respiration in the system was 3.78, and the connectivity index was 0.4. The fin cycling index and the mean path length of the energy flow were 4.92% and 2.57%, respectively, which indicated that the ecosystem exhibits relatively low maturity and stability. The mixed trophic impact(MTI) procedure suggested that the ecological groups at lower trophic levels dominated the feeding dynamics in the Jimo coastal ecosystem. Overfishing is thought to be the primary reason for the degeneration of the Jimo coastal ecosystem, resulting in a decline in the abundance of pelagic and demersal fish species and a subsequent shift to the predominance of lower-trophic-level functional groups. Finally, we offered some recommendations for improving current fishery management practices.
基金the National Natural Science Foundation of China (No. 10671122).Acknowledgement The author would like to thank Professor Dr. U.Knauer for valuable advice and helpful comments on this paper.
文摘By End(G) and hEnd(G) we denote the set of endomorphisms and half-strong endomorphisms of a graph G respectively. A graph G is said to be E-H-unretractive if End(G) = hEnd(G). A general characterization of an E-H-unretractive graph seems to be difficult. In this paper, bipartite graphs with E-H-unretractivity are characterized explicitly.